📋 Description

This PR addresses Issue #55 by adding a comprehensive .env.example file to document all environment variables required for the GitHub MCP SSE Server configuration.

🎯 Changes Made

✅ Added .env.example file with:

• GitHub API Configuration: GITHUB_TOKEN with clear instructions
• Server Configuration: MCP_SSE_PORT, MCP_TIMEOUT
• Logging Configuration: LOG_LEVEL with available options
• CORS Configuration: CORS_ALLOW_ORIGIN
• Transport Configuration: USE_MULTIPLEXING_SSE with detailed explanations
• Rate Limiting Configuration: Comprehensive rate limiting options

📝 Documentation Features:

• Clear comments explaining each variable purpose
• Instructions on where to generate GitHub tokens
• Default values for all configurable options
• Inline documentation for complex configurations

🔧 Environment Variables Documented

# Core Configuration
GITHUB_TOKEN=your_github_token_here          # Required GitHub API token
MCP_SSE_PORT=3200                           # Server port
MCP_TIMEOUT=180000                          # Request timeout (ms)
LOG_LEVEL=info                              # Logging level

# Advanced Configuration
CORS_ALLOW_ORIGIN=*                         # CORS origins
USE_MULTIPLEXING_SSE=false                  # SSE transport mode

# Rate Limiting
RATE_LIMIT_WINDOW_MS=900000                 # Rate limit window
RATE_LIMIT_MAX_REQUESTS=100                 # Max requests per window
RATE_LIMIT_SSE_MAX=5                        # Max SSE connections
RATE_LIMIT_MESSAGES_MAX=30                  # Max messages per minute
DEFAULT_USER_RATE_LIMIT=1000                # Default user rate limit

🛡️ Security Benefits

• Prevents credential exposure: Clear template prevents accidental commits of tokens
• Consistent configuration: Standardized setup across environments
• Documentation: Reduces configuration errors and setup time
• Best practices: Follows 12-factor app configuration principles

🔍 Verification

• .env.example file created with all necessary variables
• Clear documentation and comments for each variable
• .gitignore already properly configured to exclude .env files
• All variables from codebase analysis included
• Default values provided for optional configurations

📚 Related Issues

Closes #55 - 🟡 MEDIO: Falta archivo .env.example para documentar configuración

🧪 Testing

• Verified file structure and content
• Confirmed all environment variables are documented
• Validated against issue requirements
• Ensured no sensitive information in template

📖 Developer Impact

Before: Developers had to guess environment variables from code
After: Clear documentation makes setup straightforward and prevents configuration errors

This improvement significantly enhances the developer experience and reduces onboarding time for new contributors.